DAST On-Demand Scan - View Scans - Empty tabs

Why are we doing this work

Once the on-demand scans index page has been created, we'll create the page's tabs with their empty states.

Relevant links

• Design Issue
  • Design 1

Non-functional requirements

• Testing:
  • Link to on-demand scans form renders properly.
  • Each tab renders the empty state with the correct text.

Implementation plan

• Render a link to the on-demand DAST scan form in the top-right corner.
• Render a GlTabs component.
  • It replaces the primary empty state based on a condition (dummy boolean for now).
  • It renders 4 tabs: All, Running, Finished, Scheduled.
  • The 3 non-default tabs render specific empty states:
    • Running: There are no running on-demand scans.
    • Finished: There are no finished on-demand scans.
    • Scheduled: There are no scheduled on-demand scans.